Nicotinic acid adenine dinucleotide phosphate NAADP

NADP can be converted to nicotinic acid adenine dinucleotide phosphate (NAADP), which has distinct functions in the regulation of intracellular calcium stores. The studies of these new roles of NAD(P) in metabolism are in their early stages, but they might soon help to better understand and explain the symptoms of niacin deficiency ( pellagra) [1]. 

Brailoiu, E., Patel, S. and Dun, N. J. Modulation of spontaneous transmitter release from the frog neuromuscular junction by interacting intracellular Ca2+ stores critical role for nicotinic acid-adenine dinucleotide phosphate (NAADP). Biochem. J. 373 313-318, 2003. 

Yusufi ANK, Cheng J, Thompson MA, Chini EN, Grande JP 2001 Nicotinic acid-adenine dinucleotide phosphate (NAADP) elicits specific microsomal Ca2+ release from mammalian cells. Biochem J 353 531—536... 

The nicotinamide nucleotide coenzymes function as electron carriers in a wide variety of redox reactions. In addition, NAD is the precursor of adenine dinucleotide phosphate (ADP)-ribose for ADP-ribosylation and poly(ADP-ribosylation) of proteins and cADP-ribose and nicotinic acid adenine dinucleotide phosphate (NAADP). They act as second messengers and stimulate increases in intracellular calcium concentrations. 

NADI, the phosphorylated version of NAD, is converted in the cell to nicotinic acid adenine dinucleotide phosphate (NAADP). NAD cannot be used directly for this purpose. NAADP seems also to be used as a cell-signaling molecule, and to pnwokea burstof intracellular calcium ions (Aarhus ef ai, 1996 Dousa ct aL, 1996),... 

Fig. 6.9 Reactions of ADP ribosyl cyclase. Structures of NADP, nicotinic acid adenine dinucleotide phosphate (NAADP) and cyclic ADP-ribose phosphate (cADPRP). ADP-ribosyl cyclase, in base ex-...

RYR. 2, PLC/lnsP3 evoked release of Ca2+ from lnsP3 receptors or ryanodine receptors. 3, cyclic ADP-ribose (cADPR)- evoked Ca2+ release. 4, nicotinic acid adenine dinucleotide phosphate (NAADP) evoked Ca2+ release. 5, Ca2+ release evoked by sphingosine. 6, Ca2+ release from mitochondria. 

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